While some analysts are predicting that AV will deliver significant electoral benefits for the Liberal Democrats the latest analysis by researchers at the University of Warwick suggests otherwise. The Warwick researchers simulate the 2010 election under the Alternative Vote and found that the Liberal Democrats would have gained only 10 seats or less if AV had have been used.

Dr David Hugh-Jones a researcher in the University of Warwick’s Centre for Competitive Advantage in the Global Economy (in the University’s Department of Economics) carried out this analysis to refine the view other research by Professor David Sanders at Essex which suggested the Liberal Democrats would gain about 30 seats if AV had have been used in the last general election.

The University of Warwick research predicts much more modest gains for the Liberal Democrats on the order of 10 seats or less if the last general election had been run under AV.

Estimating AV election results is difficult, because the AV system uses information on voters' second, third and further preferences over candidates, and these are not recorded by the current First Past the Post electoral system. The study led by Professor David Sanders at Essex overcame this by using a data from a simulated AV ballot paper included in the 2010 British Election Study. That team “reran” the 2010 election using that simulated AV ballot to see where people would have put their second and third preferences however they neglected to account for the fact that the simulated AV ballot paper also clearly shows that AV radically alters what people put as their first preference. The simulated ballot showed that only about 75% of Liberal Democrat voters put the Liberal Democrats as their first choice in the AV election, compared to over 90% of Labour and Conservative voters.

The Warwick researchers also “reran” the 2010 election using the simulated AV ballot but did also use the information that showed how AV would have changed people’s first preferences suggested by the simulated AV ballot .

University of Warwick researcher Dr David Hugh-Jones said:

“The Essex led research results show a fairly substantial gain for the Liberal Democrats, though their seat share still remains far below their vote share. By contrast, my results suggest that electoral changes from AV may be marginal: compared to the FPTP result, about 10 seats are gained by the Liberal Democrats, and about 10 seats are lost by the Conservatives. Under a different assumption about second and third preferences, the changes are even smaller. This new research suggests that AV would have made only a marginal difference to the election result. AV looks like a small step rather than a massive revolution. It also seems unlikely that it will lead to many more coalitions, or to extremists getting elected."